Szmuszkovicz U.S. Pat. No. 4,145,435 discloses some cis- and trans-N-(2-aminocycloaliphatic)-2-arylacetamide derivative compounds, e.g., N-[2-(N',N'-dimethylamino)cyclohexyl]-N-methyl-2-(4-bromophenyl)acet amide and trans-N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl]-2-(3,4-dichlorophenyl)acet amide, which have potent analgesic activity; the preferred compounds thereof have, in addition, only low to moderate apparent physical dependence liability compared to morphine and methadone. That Szmuszkovicz U.S. Pat. No. 4,145,435 also describes some prior art patent and publication background that may be of interest herein also.
Also, Szmuszkovicz U.S. Pat. No. 4,098,904 discloses some cis- and trans-N-(2-aminocycloaliphatic)benzamide compounds, e.g., N-methyl-N-(2-aminocycloaliphatic)benzamide compounds, e.g., N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl]-3,4-dichlorobenzamide which have potent analgesic activity, making them useful for relieving pain in warm-blooded animals. That U.S. Pat. No. 4,098,904 also discloses background patents and publications which may be of interest herein.
Lednicer U.S. Pat. No. 4,212,878 discloses some N-[(1-amino-4-(mono- or di-oxygen group substituted)cyclohexyl)methyl]benzeneacetamide derivatives, e.g., 2-(3,4-dichlorophenyl)-N[8-(1-pyrrolidinyl)1,4-dioxaspiro[4.5]dec-8-yl)met hyl]acetamide, which also have analgesic drug properties with lower physical dependence liability characteristics than morphine or methadone. That Lednicer patent also refers to what is now Lednicer U.S. Pat. No. 4,065,573 which discloses some 4-amino-4-phenylcyclohexanone ketal compounds, e.g., 4-(m-hydroxyphenyl)-4-(dimethylamino)cyclohexanone ethylene ketal and 4-(m-hydroxyphenyl)4-(n-butylmethylamino]cyclohexanone ethylene ketal, which are useful for relieving pain in animals, some of which compounds exhibit narcotic antagonist activity.
Other references are listed in the accompanying prior art statement.
Some concern has been expressed about possible dysphoric side effects of some of these prior art compounds when used as analgesic drugs. Those skilled in the art continue to search for new and more advantageous analgesic compounds.